622337 Nordyne 24 VAC Control Transformer – 120 VAC to 24 VAC, 40 VA
622337 Nordyne 24 VAC Control Transformer – 120 VAC to 24 VAC, 40 VA
Product Overview
622337 is a genuine OEM Nordyne control transformer that steps down 120 VAC line voltage to 24 VAC control power at 40 VA. Engineered for M2 and M3 series furnaces, it delivers stable, low-noise 24 VAC for thermostats, gas valves, and control boards. Its vertical quick-connect spade terminals simplify field replacement and eliminate the need for soldering or pigtails.
Technical Specifications
| Specification | Detail |
|---|---|
| Primary Voltage | 120 VAC, 50/60 Hz |
| Secondary Voltage | 24 VAC, 50/60 Hz |
| Power Rating | 40 VA |
| Secondary Current | 1.67 A |
| Terminals | Four 1/4″ male quick-connect spades (2 primary, 2 secondary) |
| Mounting Orientation | Snap-in vertical chassis mount |
| Insulation Class | B (130 °C) |
| Ambient Operating Range | –40 °F to 140 °F (–40 °C to 60 °C) |
| Net Weight | 1.8 lb |
Cross-Reference Part Numbers
| OEM Part Number | Replaces |
|---|---|
| 622337 | 620688 |
| 620776 | |
| 620860 | |
| 621079 | |
| 621329 | |
| 621440 | |
| 621486 |
Compatibility
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Nordyne M2 and M3 series gas furnaces
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Nordyne-Miller, Intertherm, and Coleman furnaces using a 120 VAC → 24 VAC, 40 VA transformer
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Private-label units built on the same chassis requiring 24 VAC control power
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Any HVAC system originally equipped with part numbers 620688, 620776, 620860, 621079, 621329, 621440, or 621486
Always verify your furnace data-plate transformer VA rating and chassis-mount footprint before ordering.
Technician Notes
-
De-energize all power at the service disconnect and lock out/tag out before servicing.
-
Remove the furnace control-panel cover to access the existing transformer.
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Photograph or label each spade-terminal connection to preserve original wiring orientation.
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Pull the old transformer straight out of its mounting clips; slide spade connectors off the lugs.
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Snap the new 622337 transformer into the chassis-mount bracket—ensure a firm, vibration-free fit.
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Reattach primary (120 VAC) and secondary (24 VAC) leads to their matching quick-connect spades.
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Restore power and measure secondary voltage with a multimeter; expect approximately 24 VAC with no load.
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Call for heat or cool; confirm stable 24 VAC under load and verify all control circuits (thermostat, gas valve, safety interlocks) operate correctly.
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Inspect terminal tightness and wiring harness strain relief to prevent future loose connections.
Transformer for M2 and M3 series furnaces. 120V input (load), 24V output (line). 40VA, 50/60HZ.
Replaces 620688, 620776, 620860, 621440, 621079, 621329, 621486, 621486R, 104445000 & DUB20054401.